Predicting the elastic properties of closed-cell aluminum foams: a mesoscopic geometric modeling approach

The biggest challenge in predicting the elastic properties of closed-cell aluminum foams is capturing the actual geometrical and topological characteristics precisely and efficiently such that the model can be used to predict the mechanical properties of the real foam accurately. This paper presents a mesoscopic modeling approach for constructing a geometric model that captures these characteristics and can be used to predict its elastic properties. The modeling approach introduces a new method for finding the number of seeds based on the cell diameter distribution and an algorithm for computing and assigning the irregular cell wall thickness based on reverse bubble growth. Results from the foam models developed in this work were found to have better accuracy in capturing the geometrical and topological characteristics of the real foam. All foam models generated by the proposed modeling approach have the same cell size distribution and irregular cell wall distribution as the real foam. The models have cells with around 14 faces with 5 edges on each face which is similar to real metal foams and naturally occurring foams. Numerical results from the foam models showed a better accuracy in predicting the relative Young's modulus of the real foam than the generic Lag uerre-Voronoi, Kelvin, and Grenestedt models.